Saturday, April 25, 2015

If it’s April, it must be Austria. So far, our plan to travel less now we are back in the UK seems to be being mostly honoured in the breach. To be fair, we are travelling fewer miles and suffering less jet lag, and both these factors probably help to explain why we are still spending quite a lot time away from home. As you may have seen, we entered the Vienna Marathon (and half), and the subsequent need for recovery gave us a good excuse for week of lazily sitting around, eating and drinking. It didn’t turn out quite as lazy as we’d expected…

Somehow we managed to get in for 8:30 on Monday morning, where I started off in a hydrology session about data, models, model building and prediction. I had put my poster into this, not because it was really that great a fit but because hydrologists have been thinking about these issues for a lot longer than most climate scientists and have a range of interesting ideas. Keith Beven is one of the famous names in the field and he gave an good general talk about determining when and whether models might be fit for purpose. The session was a good choice for me, I picked up a couple of new (to me at least) ideas that might well come in handy. There was an unfortunate clash with an NP session on building models from data, so jules attended that one. In the afternoon there was nonlinear time series analysis, wavelets and the like, including Bo Christiansen explaining his 2014 paper on regression, which I found much more digestible as a presentation than I had when reading the paper.

Tuesday started with the data assimilation session, including some steady progress towards the practical use of particle filters. To be honest, I’m surprised how long this has been in the pipeline, as some bold claims were being made for it several years ago. Another interesting talk was Alexis Hannart on the use of data assimilation in detection and attribution. Two relevant papers are here and here. I’m not sure exactly what it all means yet but it’s a promising idea at least. jules went to the seasonal/decadal prediction session and reported that it was the same as usual…some spots of skill but at longer time scales this is essentially due to the forced response rather than the precise initialisation.

Wednesday was the big paleoclimate day, with jules’ co-organised session including the Milankovitch Medal lecture, all the latest paleo research and some work specifically linking past and future climate change. However, before that, we both managed to see Bjorn Stevens’ talk on why aerosol forcing is lower than most people had previously thought. This was a longer and more detailed version of what he had said at Ringberg, and seemed fairly convincing to me. Then on to the paleo, which started with Paul Valdes giving a great medal lecture covering several new pieces of work from his group covering multiple time scales over the last 500 million years. We were amused by one of the questioners afterwards managing to drop in the line “As I said in my medal lecture a few years ago…”. In the rest of the session, there was interesting stuff on re-interpreting some ocean proxies which brought them more into line with other evidence from data and models, and some analysis of model simulations.

By Thursday i was flagging a bit, and the program was a bit less busy. I went to the sesssion on the Last Millennium, where someone had discovered a new volcanic eruption, someone else was debating about the significance and cause of various wiggles, and several others were considering the question of what we can really expect to learn from the proxy data anyway. Rob Wilson had a potentially provocative title along the lines of “Are the tree rings fit for purpose?” and I was hoping for a bit of a bunfight but he pulled his punches a bit. After a long, large and loud dinner on Thursday evening with the Bristol crowd, Friday was fortunately very quiet. The highlight was the EGU Great Debate on open access publishing, which can be streamed from the EGU web site. A couple of commercial publishers on the panel tried their best to justify the continuation of closed journals with the rather bizarre justification that scientists wanted them (only because they can’t/won’t pay the extortionate open access fee!), but even they acknowledged the inevitable growth of the open access movement. Uli Poschl was fairly direct without being too aggressive, saying that we (scientists) were going to do it anyway, so commercial publishers could either adapt or fail. There were a few red herrings raised in the discussion, but overall it was an interesting event. After 4 consecutive evenings of dining out with various people, we gave the convenors’ party a miss and had an early night instead.

Throughout the week, we gained the impression that a lot of younger scientists had not attended and their work was instead being presented by their supervisors. This rather undermines the EGU goal of trying to allow younger scientists to gain some visibility. No good picking a couple of early career scientists for your oral session if they don’t have the funding to turn up! But of course there have always been absentees and I don’t know if this is really a trend or just chance in what we happened to see. The conference attendance was marginally down on previous years, but there’s no sign of a trend there either.

Throughout the week the poster sessions were enjoyable and well-attended, though I wish all divisions would adopt the CL convention of using the evening session for posters only, and not scheduling talks. It would have been more convenient to be able to talk to all the poster presenters at the same time.

Viennese food was fun as always, perhaps a bit less exciting now we are not in Japan and can get big hunks of meat and good beer any time we like. What with no longer being bound by Japanese rules, we decided to stay an extra day in Vienna at the end. As it happened, it was a cold and windy day, we didn’t really have the energy for much sightseeing but did walk most of the way round the town. In the evening, we found a concert in Karlskirche – Mozart’s Requiem with an orchestra on traditional instruments. The singers were very good but the pews were very hard and the accoustics were rather odd. It was an interesting experience that I wouldn’t rush to repeat. Next year the Vienna marathon is a week earlier than the EGU, so we certainly won’t be doing both of them, and quite possibly neither.

Thursday, April 23, 2015

Better late than never perhaps, Bikebiz reports that Trek has issued a 1 million bike recall notice relating to QRs loosening and causing crashes. There's still plenty of misdirection and obfuscation, of course. Trek's notice refers to QRs that can open beyond 180 degrees such that the lever gets caught in the disk or wheel. But all their original arguments were that if correctly installed, the QR cannot come loose in the first place. Sadly this is not true, as has been amply shown in practice and supported by the simple theory that I presented a decade ago. That is, under the strong transverse forces that are generated in normal use of disk brakes, the phenomenon of vibration loosening may result in unscrewing of the nut and loosening of the QR. This is elementary engineering that has been known for decades, though poor design and maintenance means that it still crops up occasionally, eg as the cause of this rail crash a few years back.

The last version of my web page discussing this seems to be on the wayback machine here. Perhaps I should get round to hosting it somewhere again. But it's old news, and all I got from it was a load of grief from ignorant numpties who didn't care if others were seriously injured by this shoddy design. Shame it took another case of paralysis before Trek started to take it seriously. Hope there aren't too many more, but at this point it's hard for me to do more than shrug and say "told you so". The QR system is simply inadequate for bicycles equipped with disk brakes. It was never designed to take the forces involved, which are massively greater (and in a different direction) to those generated with conventional rim brakes. Fiddling around with it to try to patch up the problems is no alternative to just implementing a sensible robust design (of which there are several available).

Tuesday, April 14, 2015

Saw a runner wearing a t-shirt with that written on her back half-way round the Vienna marathon on Sunday...about 10km further on I was thinking I should have asked her where she bought it so I could get one too!

As I mentioned before, the coincidence of Vienna marathon and EGU General Assembly was too good to miss so we signed up some time ago. But especially with the surprise run at Chesterfield,
I didn't have massive motivation for serious training and over the last few months we've also
been a bit busy with trips both professional and personal. So
although I started out with good intentions, my mileage was well down on
what I managed last time, though doing some running with the local
club did increase the intensity. Jules has been an even more
intermittent runner through injuries. But we thought it would be fun to take part in this big event anyway, having watched it a couple of years ago. We came out to Vienna on Friday, and are staying in a lovely apartment (found via Airbnb) on Nestroyplatz, handy enough for the town centre and ideally placed for the EGU and marathon (which started at the same place). Picking up our race numbers the day before the race was a bit of a pain to be honest - why can't they just post them? - but having seen plenty of Vienna over the years we were not desperate to traipse around touristing and apart from my early morning jog along the canal we had a restful Saturday.

The start was sunny, it wasn't really hot but was slightly concerning that we were not at all cold despite setting out from our apartment around 8am in mininal race gear and standing around on the start for a full 30 mins. The clothes trucks were timetabled to shut at 8:15 so we didn't use them, in reality they stayed at least until 8:35. For future reference, we could have turned up rather later and had no problems getting to the start on time.

The start was well organised with the main body of runners starting off in three waves, so no-one had huge delays getting going as has happened before (especially Tsukuba for us). I was in the first wave just behind the handful of elites who went off a minute ahead and were soon out of sight.

Despite the limited number of miles in my legs I
did think I'vd been running reasonably fast recently (including 25k in sub-3h pace on a windy day), and Vienna is fairly flat, so I had hopes of some improvement over my previous best time which had been on a hilly course with a very thin field. I didn't have any detailed race plans other than to limit my pulse to about 150 over the first half, but had also worked out that setting out at 21 mins per 5k would bring me in at about 2:58 even allowing for a slight slowing. The 2nd kilo had a big downhill so I wasn't all that concerned when I started off a bit quick and my official 5k split times through to 30k were an impressively smooth 20:07, 21:01, 21:00, 21:00, 20:24, 21:00. I knew I was going a bit fast (though not exactly how fast: my Garmin was stupidly set up so it only showed mins not seconds past the first hour, and its calibration was also significantly off from the course markers) but I felt like I was holding myself back a bit, tracking behind runners, hiding out of the wind, taking on lots of water and food (home-made Kendal mint cake) and running quite easily within myself. However by half-way (which I went through in the optimistic time of 1:27:30) my quads were starting to hurt a bit and although I pushed on for a while it all got a bit much and my legs pretty much fell off around 34k. I've never run 8k on such sore legs before and don't intend to again! Lost about 4 mins over the final stages and jogged over the line in 3:00:38, almost a minute down on Chesterfield and feeling very relieved that I got the sub-3h
time already so I don't need to have another go.

Not a pretty sight approaching the finish!

The hot sunny day might also have
had something to do with my fade, especially after preparing by training
though a Yorkshire winter - only a few short weeks ago we were running
through snow, Sunday we ran past a shop sign indicating 20C! (Historical met obs say 14C at the start rising to 18C at the end but those are of course for air temp in the shade, which was scarce.) Looking through the results, an awful lot of people seemed
to fall apart towards the end, which was probably a combination of the
heat and some rather exposed windy sections as the field spread out. Even some of the elite women lost 10 mins or more on the second half, which makes my own +5:38 split seem relatively tame by comparison. Jules had a fairly steady run for her half marathon, also fading a bit in the heat but not as badly as many around her. So although with hindsight I obviously set out a bit too fast, it wasn't by a huge margin. On a cooler and calmer day I might have got away with it. My position of 206 in the men (21st in my age category) would also have been comfortably under 3h on any of the previous 5 years at least.

This time the ribs and beer came after the race, which may have been
the real reason for my downfall :-) I'd say more research is needed on this point, but
that would imply another marathon which is not on the cards for a while
at least. There are three peaks close to where we live in Settle, it would be rude not to visit them some time...

And now we are trying to snooze in lecure rooms, though some of the talks have already been interesting and potentially useful, which makes it difficult!

A follow-up more targeted towards climate sensitivity was arranged for this year, and it seemed only fair for me to go this time. Actually, it was not so much fairness, but rather that the workshop seemed to be somewhat more closely aligned with my work and interests than hers. So although we were both invited this time round, we decided that only I would attend. This ended up with me having the undeserved privilege of two slots for presenting two rather distinct aspects of our research during the week.

I must admit I went with somewhat moderate expectations, as a number of workshops I’ve attended in the past seem to consist mostly of people talking about their own personal interests without really making progress towards shared understanding or common goals. This one turned out to be really good, however. The sessions were arranged into relevant themes and the organisers and discussion leaders did a good job of keeping things focussed around what really mattered for understanding climate sensitivity. We started with some talks about the framework(s) underlying the concept of climate sensitivity, and some discussion of their limitations. Most significantly to me, this included some strong evidence that the concept of a constant (state-independent) feedback under warming was too limited, with evidence pointing towards an increase in sensitivity with warming, and some difference between forcings. It’s one thing to be vaguely aware of some literature around this topic, but quite another to hear and participate in direct discussion with the people generating the main results. In summary, evidence based on recent obs (ie 20th century temperature trend and energy balance) do on the face of it point towards a rather low sensitivity, but adjusting for the likely change in feedback would push the estimate of equilibrium response up somewhat.

Next up was paleo, where I was due to present what is primarily jules’ work linking past to future. Unfortunately Ayako was also absent, but she did manage to send me some slides (as did Dan Lunt) and so I tried to weave them in to a somewhat broader perspective than I had originally intended. State dependence of sensitivity is a big issue here, though the paleo record does seem broadly consilient with what we see in the models and recent record. It’s hard to see how the climate can have changed as we see in the past if the sensitivity to radiative forcing (in its most general sense) was either negligibly low or extremely high.

The other main focus area was the more process-based understanding of how feedbacks (especially in the clouds, which are the dominant source of our uncertainty) worked in the real world, and how well these were simulated in models. I found this the hardest to follow and certainly couldn’t contribute usefully to the discussion, but there seemed to be a clear feeling that it was hard to justify large negative feedbacks that would bring the sensitivity below about 2C, especially when some positive feedbacks (on top of the well-established Planck response and water vapour/lapse rate feedback) seem to have been identified with some confidence. On the other hand, high sensitivity would seem to require a number of things to combine unhelpfully, which may not be impossible but is certainly not anticipated. There was also a lot of discussion about the absence of extreme models (at either end) from the CMIP archives, and what if anything could be inferred from this. I certainly subscribe to the view that this is some evidence in favour of the CMIP range being reasonable, as firstly it seems quite hard to build extreme models in the first place, and secondly, they tend to behave a bit strangely when they are investigated in any detail. But it is also possible that people converge to some extent through social effects that have no sound basis.

There was a lot of discussion on how to synthesise the different lines of evidence, and my second presentation focussed on this topic. I’m hoping to do more on this soon, as there seems to be plenty of material to revisit and improve the rather superficial analysis that we did several years ago. There are plans to revisit the workshop topics (and venue) in three years to see where have got to, which I look forward to very much. Gavin also has a summary on RC and I fully endorse his comments about the value of meeting in person (though I also think that there’s plenty of scope to expand video-conferencing, especially to enable wider access without the need for lots of travelling). Most of the talks are also on-line for anyone interested.

The food and accommodation was spectacular. The food was far better than one can usually expect in a workshop situation, with a wide range of excellently cooked fish or meat for both lunch and dinner (with the odd bottle of beer thrown in on top). It might have been a little overwhelming for some but I can handle just about anything for 5 days, helped by fitting in a couple of runs down to the lake and back. And I think all attendees found the accommodation very satisfactory too. I think I was a little luckier than some, having one of the big old suites on the first floor. I’ve no idea what I did to deserve this privilege, and was a little concerned on the castle tour, when the first room we were taken into was the one next to mine, and then we walked along the corridor…into the room just on the *other* side of my (embarrassingly untidy) room. Phew. Here it is in neater guise.

On the afternoon off, we took a cable car trip up a neighbouring mountain, which had some lovely views although not sunny as it had been previously. We also had a touch of snow but nothing like last year.

And for anyone who accuses academics of hiding away in ivory towers, I can assure you that ivory was nowhere to be seen. Marble, on the other hand…